When growing sugarcane taller than normal, sometimes I have encountered air blocks separating two sugarcane blocks such that one is floating. Very odd, I don't know what causes it because I wasn't looking when it happened.

Upon closer inspection, it seems that the sugarcane does exist, but simply does not load, resulting in an air-like sugarcane block. This means that:

1. It has no hitbox
2. It is invisible
3. When breaking lower sugarcane, it still breaks
4. Upon reloading a world, it will disappear. Or appear, depending on how you think about it.
5. The block still yields sugarcane